Re: Scalloped tires?!? and parts appetite...

[newbold@banshee.camb.inmet.com (Chris Newbold)]

> From: adams@churchill.columbiasc.ncr.com

> > So, what's the deal? Is this really just a random thing, or is it indicative
> > of some other problem? Driving too hard? :-) Darned annoying, since the
> > tires still seem to have about half their life left; the shakes gone from
> > the front now, but I can still feel it from the rear in the seat of my
> > pants.
> 
> No this is not random, because this is the EXACT same problem we are
> experiencing.  Our 93 90CS has ~21,5K miles and is 2 weeks from the next
> service.  At the 15K service they balanced and rotated the tires.  At this
> time we noticed a vibration and annoying noise.  The tires make a high
> pitched wakawakawaka sound at highway speeds (at least that is were it is
> noticed).  I also pay close attention to tire pressure and there are no
> syptoms of alignment or balance problems.  In our case the Audi is my
> wife's daily driver and it is not driven hard, so I place bets on the tires
> being the culprit.  I will let you know if I get any differant response
> from my dealer. 

Please do! It sounds as if your problem is slightly worse than mine, because
I seem to have been spared the wakawakawaka action; so far, anyway...

My 90CS is my daily driver, also, though I do drive it hard. I wonder if
the problem has to do with hard breaking over bumpy pavement...

> From: zm@mhcnet.att.com (Zafer Mehmood  [209])
> ...
> the tire gets scrubbed when it hits the road surface. Braking over rough
> roads accentuates this scalloping since the brakes slow down the tire
> considerably faster while the tire is up in the air and the now slower
> tire hits the (relatively) faster moving ground - and another scoop of
> rubber is scrubbed off the tire.

Now, I doubt that we have weak shocks, but maybe the car is light enough
at the rear with only the driver on board to cause a problem....

-Chris